This invention relates to an improved railway car door operator assembly which is mountable on a self-propelled vehicle for selectively opening and closing railway car doors.
A common problem with railway car doors is that a substantial amount of force is required either to open the door or to close the door. The utilization of a vehicle to open or to close a door is well recognized. Three prior art patents show devices attached to a forklift truck for opening or closing a railway car door. Those prior art patents are: U.S. Pat. No. 4,149,644, entitled, “Fork Lift Truck Attachment” issued Apr. 17, 1979, to Richard C. Fuller; U.S. Pat. No. 4,160,509, entitled, “Freight Car Door Opener” issued Jul. 10, 1979, to Ralph V. Switzer; and U.S. Pat. No. 4,290,730, entitled, “Attachment For Fork Lift” issued Sep. 22, 1981, to James A. Weaver. The devices shown in the three prior art patents are effective in a situation wherein the truck may move in a straight line the length of the distance required for opening or closing the door. However, there are situations wherein the truck is prohibited from moving in a straight line. For instance, if a loading dock is enclosed, that is, it is under a roof with walls and the walls have openings just large enough to align with the opening of a box car. In those instances, the known freight car door openers may not be used effectively due to the space limitations interiorally of the loading dock.
It is an object of the present invention to provide an improved railway car door operator assembly which is mountable on a self-propelled vehicle, such as, a forklift truck either to open or to close a freight car door in a minimum of space. Other objects and uses of the present invention will become readily apparent to those skilled in the art upon perusal of the following specification in light of the accompanying drawings.